The Study On Removing VC And KGA In Wastewater By Adsorption

The adsorption and its mechanism of which VC and KGA in wastewater were adsorbed onto mineral materials such as sepiolite and bentonite are studied in this dissertation. As an important physic-chemical method, adsorption has already been used widely because it is simple and efficient; especially it is effective in treating wastewater containing low concentration pollutants. The key to adopt the adsorption method on treating wastewater is to choose the suitable adsorbents. In the experiments, sepiolite and bentonite with large superficial area and micro holes are chosen as absorbents.The main factors affecting VC and KGA absorption onto sepiolite and bentonite are: the adsorbent-aid, initial pH, the dosage of adsorbent, the initial concentration adsorbate, and so on. The following conclusions can be obtained.(1) When adsorbent and adsorbent-aid use at the same time, the adsorbing effect is better than that without adsorbent-aid. The removal rate of VC and KGA is varied when the dosage of adsorbent-aid is changed;(2) The adsorbing effect of bentonite activated by microwave is better than that of original bentonite;(3) When VC is adsorbed by adsorbents, the effect is better at the condition of 6 min, pH5.5, PAC0.8g/L, sepiolitel5g/L; the lower the initial concentration of adsorbate is, the better the adsorbing effect;(4) When KGA is adsorbed by adsorbents, ,the effect is better at the condition of sepiolite 15g/L, PAC0.8g/L, pH5, 5min;The better the effect, the lower the initial concentration .According to results of SEM, X ray diffraction analysis, and granularity analysis, the mechanisms are studied. When mineral materials and adsorbent-aid are used to adsorb VC and KGA, there exist electrostatic adsorption, superficial adsorption and microhole adsorption in the process. The using of adsorbent-aid not only changed the superficial voltage but also conjugated adsorbate.